This invention relates to the integration of three-dimensional computer graphics and a two-dimensional image to provide a realistic three-dimensional virtual reality experience.
The display of a three-dimensional virtual reality world to a user requires considerable computation power, and it is typically costly to develop the necessary highly detailed models required for doing so. In order to simplify the problem, two-dimensional images, such as videos or photographs, may be used to represent or simulate portions of the three-dimensional world. A great reduction in computation power and cost can be achieved by such an arrangement.
A limitation of such a world occurs when a user moves within the world and views the world from a location different than the original context of the two-dimensional image which has been carefully calibrated to xe2x80x9cfit intoxe2x80x9d the world. View changes, such as from a location different than the image""s ideal viewing point also known as the xe2x80x9ccenter of projection,xe2x80x9d result in the image not aligning or fitting well with surrounding objects of the three-dimensional world. Display techniques, however, to deal with such viewpoint changes are described in applicant""s co-pending application which discloses manipulating the two-dimensional image through the use of so-called xe2x80x9cpyramidic panel structures.xe2x80x9d More specifically, the two-dimensional image is manipulated so as to adjust the image""s vanishing point(s) in accordance with the movement of the user. In this manner, as the user moves away from the ideal viewing point, warping acts to limit the discontinuities between the two-dimensional image and the surroundings of the world. However, these latter novel display techniques have the disadvantage that they work primarily for so-called xe2x80x9ccorridor-likexe2x80x9d two-dimensional images, such as roads, or streets, wherein parallel features appear to converge at a so-called xe2x80x9cvanishing point.xe2x80x9d
Although in my co-pending application, so-called xe2x80x9cpyramidic panel structuresxe2x80x9d are employed to adjust the image""s vanishing point(s) in accordance with the movement of the user, such structures have the disadvantage that they work primarily for xe2x80x9ccorridor-likexe2x80x9d two-dimensional images. I have recognized that, in accordance with the principles of the invention, viewpoint changes may also be dealt with by partitioning the two-dimensional image into polygon partitions, each corresponding to a surface being depicted in the image, and then coupling the vertices of the polygon partitions with the movement of the user so as to limit distortions. More specifically, image points located farther away from the view plane oft he user move more closely with the movement oft he user""s current view point than those image points located closer. In this manner, as the viewer moves away from the image""s ideal viewing point, IVP, the resulting warping in the image acts to counteract and limit distortions. Importantly, in this latter approach, two-dimensional images are not treated as so-called xe2x80x9ccorridor-likexe2x80x9d images, thereby allowing a wider variety of two-dimensional images to be used with the present invention.